The use of closure devices for fastening storage containers, including plastic bags, is generally known. Furthermore, the manufacture of closure devices made of plastic materials is generally known to those skilled in the art, as demonstrated by the numerous patents in this area.
A particularly well-known use for closure devices is in connection with flexible storage containers, such as plastic bags. In some instances, the closure device and the associated container are formed from thermoplastic materials, and the closure device and the sidewalls of the container are integrally formed by extrusion as a single piece. Alternatively, the closure device and sidewalls of the container may be formed as separate pieces and then connected by heat sealing or any other suitable connecting process. In either event, such closure devices are particularly useful in providing a closure means for retaining matter within the bag.
Conventional closure devices typically utilize mating fastening strips or closure elements, which are used to selectively seal the bag. In addition, sliders may be provided for use in opening and closing the fastening strips. The sliders may include a separator which extends at least partially between the fastening strips. If the slider is moved in the opening direction, the separator divides or deoccludes the fastening strips and opens the bag. If the slider is moved in the closing direction, the slider closes or occludes the fastening strips.
When the slider is at the closed end of the bag, the separator is still positioned between the fastening strips and, thus, the fastening strips at the closed end of the bag may not be fully occluded. If the fastening strips are not fully occluded the bag may allow air to enter or the bag may allow the contents of the bag to leak from the bag. These situations are not desirable. The present invention provides a solution to this problem.